abstract class CartesianPoint {
  get first;
  get second;
}

abstract class PolarPoint {
  get rho;
  get theta;
}

class Point implements CartesianPoint, PolarPoint {
  final String first;
  final String second;
  final int rho;
  final int theta;

  Point(this.first, this.second, this.theta, this.rho);

}


